Automatic cut-out for secondary batteries



No. .s07,|24. Patented July l2, I898.

' w. L. NEGBAUR.

AUTOMATIC CUT-OUT FOR SECONDARY BATTERIES.

' (Application filed Feb. 19, 1897.)

(No Model.)' 2 Sheets-Sheet l.

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Wil a s 5 e s Iniyeifnr N0.607,I24. Patented July 12, I898. W. L. NEGBAUR.

AUTOMATIC CUT-OUT FDR SECONDARY BATTERIES. (Application filed Feb. 19, 1897.)

(N0 Model.) 2 Sheets-Sheet 2.

UNTTnio STATns PATENT @rricm \VALTER L. NEGBAUR, OF BROOKLINE, MASSACHUSETTS.

AUTOMATEC CUT OUT FOR SECONDARY BATTEREES.

SPECIFICATION forming part of Letters Patent No. 607,124, dated July 12, 1898.

Application filed February 19, 1897. Serial No. 624,233. (No model.)

To aZZ whom it may concern:

Be it known that I, IVALTER L. NEGBAUR, a citizen of the United States,residing at Brook- 1ine,in the county of Norfolk and State of Massachusetts, have invented certain new and useful Improvements in Electric Switches, of which the following is a specification.

My invention relates to electric switches, and more especially to an automatic switch for use in connection with a dynamo and a storage battery arranged to generate and u tilize electric energy, the object of my invention being to provide a switch which shall automatically control the battery or working circuit by closing the same whenever the voltage of the dynamo reaches a predetermined constant excess over that of the storage battery and by breaking said circuit whenever the voltage of the dynamo in decreasing reaches that of the storage battery or just before that point, so that the battery cannot by any possibility discharge through the dynamo, and thus waste the energy which has been stored.

To this end my switch comprises a magnetcore provided with a non-polarized armature which is arranged to operate a circuit-closer and two coils on said core arranged to oppose each other in their magnetic effects, one of said coils having impressed on it the voltage of the storage battery and the other that of the dynamo and the circuit-closer being operated by the differential eifeot of these coils, all as hereinafter more fully explained.

In the accompanying drawings, Figure 1 represents diagrammatically a preferred form of my switch, shown in connection with a dynamo and a storage battery. Figs. 2 and 3 are diagrammatic views of slightly-modified forms of my switch.

So far as my present invention is concerned the kind of dynamo used is immaterial.. The one shown in the drawings at G is a constantvoltage dynamo having a magnetic shunt 0 around its armature and opposed coils O and C on said shunt. Neither the said dynamo nor the system of which it forms a part are claimed herein, they being claimed in Letters Patent of even date herewith, granted to Joseph J. Feely and myself, for a Method of and apparatus for generating electricity, to

which Letters Patent reference is made for a full description of the construction and mode of operation of said dynamo and system.

Referring to Fig. l of the drawings, a represents the core of an electromagnet, and o the armature thereof, these parts together forming a magnetic circuit. On the core at are wound coils eand Z, the coil 6 beinga portionof a permanently-closed shunt-circuit from the terminals to b of the dynamo and the coil Z being in a shunt-circuit from the terminals of the storage battery j. The armature 0 is non-polarized and is pivoted, as shown, and carries a circuit-closer 19, which either makes or breaks the working circuit of the system, consisting of the conductors qand u, led from the terminals of the dynamo, the storage battery j, the conductors r and s, and the coil 6, hereinafter described. The circuitcloser p is normally held by the spring in in such a position as to keep open the working circuit fromthe dynamo, as shown.

The coils e and Z are wound and connected so as to oppose each otherthat is, so as to generate magnetic lines of force in opposite directions within the magnetic circuit on which they are wound-so that the resultant magnetic flux through said circuit will depend upon the difference between the voltages impressed upon the coils e and Z by the dynamo and the storage battery, respectively, and the armature 0 will operate to close the working circuit through 19 as soon as the mag netic flux thus generated is suflicient in its effect to overcome the tension of the spring 10.

In order that the battery j may not discharge throughthe coil Z when the dynamovoltage is below the storage-battery voltage and the working circuit is open, I prefer to include a supplementary circuit-closer i in the shunt-circuit which contains the coil Z. This circuit-closer i is operated by the armatnre g of a relay-magnet g which is energized by being included in a permanentlyclosed shunt'circuit from the terminals of the dynamo. This shun t-circuit is preferably the one which contains the coil 6, thus consisting of the conductors cZ, f, and 7L and the coils c and g. A spring o normally holds the circuit-closer 11 in such position as to open the circuit through the conductor 76. On the core circuit.

2 comes a I provide a third coil. 1, included in the working circuit and so connected as to gen erate magnetic lines in the same direction as the coil 0. The function of. this coil will presently appear.

The operation of the switch just described is as follows: The shunt-circuit which con tains the coils c and g, being permanently closed, has impressed upon it whatever voltage may be generated by the dynamo, and this voltage, when it reaches a predetermined amount determined by the tension of the spring n, creates sufficient magnet-ism in the relay-magnet g to operate the circuit-chaser '11. At the same time the coil 6 is caused to generate magnetic lines within the core 77., tending to operate the circuitcloserp, but not quite sufficient to do so, the spring In being properly adjusted to produce this result. The closing of the circuit through 7.; will cause the storage battery to send a current through the coil Z, the strength of which will depend on the voltage of said battery, and since the magnetic lines generated. by the coil Z are in opposition to those generated by the coil 6 the effect of the coil 6 upon the circuit-closer will be correspoiulingly diminished. Hence the armature o and eircuiteloserp will be operated to close the working circuit only when the dynamo-voltage exceeds the storage-battery voltage by an amount sufficient to cause the coil 0 to overcome the joint effect of the coil 1 and the spring '10. Upon the closing of the working circuit the coil '6 receives a current from the dynamo and adds its effect to that of the coil 6, thus producing a greater pressure of the circuit-closer p and making its contact firm and sure. The working circuit will then remain closed as long as the combined effect of the coils c and t exceed the combined effect of the coil. 1 and spring '20. lVhen the working circuit is thus closed, the coil Z will. have impressed upon it the voltage of the dynamo, which will be greater than that of the storage battery, and hence the coil Zwill exert an increased neutralizing effect on the coil 0 but this will be more than co unterbalanced by the added effect of the coil 1;. If new for any reason the voltage of the dynamo decreases, as it approaches the storage battery voltage the current in the coil 1. approaches zero, and the differential effect of the coils f and c acting against the coil Z and spring to diminishes until at some point which is necessarily reached before the voltage of the dynamo has become equal to or less than that of the battery the spring w draws back the circuit-closer 2) and breaks the working Hence it will be impossible for the storage battery to discharge through the dynamo, no matter what their respective voltages may be. A continued decrease of the dynan'io-voltage beyond the point where the working circuit is broken will diminish the magnetic effect of the relay-magnet g until the spring 11 will draw back the circuit-closer '11 and break the circuit through the conductor 7.; and its connections, and thus prevcn t a wasteful leakage of current through the same from the storage battery.

in the arrangement of my invention illustrated in Fig. 2 the coil is in a shunt from the workingcircuit instead of being in series with it, as in Fig. 1, and. hence it receives a different proportion of the total current. its function and mode of operation are, however, the same as in the arrangement shown .in Fig. 1.

in Fig. 3 I have illustrated. my invention so arranged that the core a of the switchanag net includes the core of one of the field -magnets of the dynamo,and the field-coil mounted on said field corc constitutes also the coil 0 of my switch and performs its functions. Uthei wise the arrangement shown in. Fig. 3.3 is sub stantially the same in its cmistructiou and. operation as that shown in Fig. '1.

I claim as my invention 1. An automatic electric switchv comprising a magnet-core provided with a llOll-ptdttl'lZOfl armature, a working circuit con trolled by saidv armature, and two coils on. said magnet coro wound and connected. to oppose each other, the said armature being operated by the differential effect of the said. coils, as set forth.

An automatic electric switch conqn'ising a magnet-core provided. with. a non-polarized armature, a working circuit controlled b y said armature,two coils on said ma gnet-corc wound. and connected to oppose each. other, the said armature being operated by the differential. effect of the said. coils, and arelay arranged to make and break the circuit through one of said coils, for the purpose set forth.

An automatic electric switch comp rising a magnet-core provided with a non-polarized armature, a working circuit con lil'OliOtl by said armature,two coils on said magnet-core wound and connected to oppose each. other, and. a relay energized simultaneously with one of said coils to control the circuit through the other coil, for the purpose set forth.

An automatic electric switch com n'ising a magnet-core provided with. a non-p0larixed. armature, a working circuit controlled. by said armature,two coils on said magnctcore wound and connected to oppose each other andv arranged to operate the said. armature by their differential. effect, and a third coil on said magnet-core arranged to be energized when i go a magnet-core provided with a non-polarizedthe Working circuit is closed, for the purpose IO armature, a Working circuit controlled by said set forth.

armature,two coils on said magnet-core Wound In testimony whereof I affix my signature and connected to oppose each other and arin presence of two Witnesses.

ranged to have independent voltages i1n- 1 T q pressed upon them, a relay in series With one VALT ER LEUBAUR' of said coils and controlling the circuit 'Witnesses: through the other coil, and a third coil on said N. A. DEXTER, magnet-core adapted to be energized when J. J. FEELY. 

